Question

Now I am planning the outdoor CCTV (Closed-Circuit Television) with 1000m of transmission distance. Deployment guideline in ICSA homepage (http://www.icsa.gr.jp/activity/index_07_03_gl_3.htm) recommends that in the case of pole mount the swinging angle of pole should be less than 1°when the wind speed is 60m/s. What is the ground of this numerical value and what is the swinging angle about 1000m of transmission distance?

Answer

In Infrared Communication the discrepancy of the beam axis causes the degradation of the transmission quality and the outdoor mount must have the sufficient strength in order to remove the influence of the building vibration and the wind. Our deployment guideline recommends the fixing method even in the case of the direct floor setting and the wall mount and the pole mount is also recommended for the flexibility of the setting.

Pole mount should be adopted in the short range transmission (less than 100m) because the swing of the pole causes the discrepancy of the beam axis.

The system parameter of radiation directivity and receiving area and the transmission distance will decide the pole mount condition. But the value of 1°is the result from the short range transmission between road and vehicle, and the guideline of the outdoor transmission of pole mount is based on the result from this field transmission and is performed without interception.

In the case of 1000m of transmission distance the pole mount is not suitable. The mount must have the sufficient strength, and the transmission power, the adjustment of beam axis, the receiving area and the tracking function should be considered on the whole.